1. Field of the Invention
The present invention relates to a cell reselection, and particularly, to systems and methods for reselecting a cell in a radio communication network.
2. Description of the Background Art
Generally, a radio communication network has a hierarchical cell structure (HCS) in order to receive more subscribers and to provide various services. Kinds of services supported by the cells on respective layers can be divided according to service quality and data rate.
When a cell reselection is required in a HCS radio communication network, the cell is reselected as follows, according to the conventional method. When a neighbor cell satisfying a cell reselection criteria is found, a mobile terminal sets up primary common control channel (P-CCPCH) transmitted from a base station of the neighbor cell and receives system information from the set-up P-CCPCH. The mobile terminal decides whether or not the neighbor cell is suitable for selection based on the received system information. The mobile terminal selects the neighbor cell, if the neighbor cell is be suitable for the mobile terminal.
However, if the neighbor cell is not suitable for the mobile terminal, the mobile terminal determines if another neighbor cell is suitable. That is, the mobile terminal sets up P-CCPCH transmitted from another neighbor cell and receives system information from the set-up P-CCPCH. The mobile terminal decides whether or not the other neighbor cell is suitable for the mobile terminal based on the received system information. If the second neighbor cell is not suitable for the mobile terminal, the mobile terminal continues searching for another cell.
In a radio communication network, a neighbor cell having the largest receive signal strength has a lower probability of being the cell suitable for a corresponding mobile terminal. Therefore, in the conventional cell reselection method, the P-CCPCH set up and analysis of the system information from the P-CCPCH is repeated until the suitable cell is found. Thus, in the conventional cell reselection method the load for cell reselection of the mobile terminal is increased. This results in cell reselection taking much time, and reduction in efficiency of cell reselection.